Known devices, sometimes referred to as scrubbers, are often employed to clean semiconductor wafers at one or more stages of a semiconductor device manufacturing process. For example, a scrubber may be employed to clean a wafer after chemical mechanical polishing (CMP) of the wafer. Known scrubbers employ one or more scrubber brushes that are rotated while in contact with the wafer to thereby clean the wafer.
It is also known to adjust the position of a scrubber brush relative to a wafer in response to a pressure sensor which detects pressure that the scrubber brush applies to the wafer. However, the present inventors have recognized that a scrubber is a hostile environment for pressure sensors, and that conventional pressure sensors may deteriorate during use in a scrubber and interfere with operation of the scrubber's pressure regulation system.
It would therefore be desirable to provide improved methods and/or apparatus for regulating the pressure applied to a wafer by a scrubber brush.